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1.
Urol Int ; 81(3): 252-5, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18931538

RESUMO

INTRODUCTION: Males presenting for assisted reproduction after vasectomy have a high chance of normal spermatogenesis and of successful surgical sperm retrieval. We aimed to evaluate simple percutaneous methods of retrieving sperm for intracytoplasmic sperm injection in males with secondary azoospermia due to previous vasectomy. PATIENTS AND METHODS: We analyzed a series of post-vasectomy males who presented for sperm retrieval between 1999 and 2005 and who were not being considered for vasal reconstruction as their primary method of re-establishing their fertility. RESULTS: All 132 men had sperm retrieved successfully, 97% with percutaneous methods. In seventy-five percent of the couples intracytoplasmic sperm injection was done, with a total number of 184 cycles being performed. The clinical pregnancy and live birth rates were 25 and 24%, respectively. There were no significant scrotal haematomas, and only 2 patients had postoperative pain after percutaneous sperm retrieval that required analgesia for more than 2 days. CONCLUSION: We have shown that percutaneous sperm retrieval, where normal spermatogenesis is assumed, is successful in all men following vasectomy. Percutaneous methods of retrieving epididymal or testicular sperm are inexpensive, simple and could replace open techniques in men who are not considering vasal reconstruction following vasectomy.


Assuntos
Azoospermia/terapia , Injeções de Esperma Intracitoplásmicas , Recuperação Espermática , Espermatogênese , Vasectomia , Adulto , Azoospermia/etiologia , Azoospermia/fisiopatologia , Feminino , Humanos , Nascido Vivo , Masculino , Pessoa de Meia-Idade , Gravidez , Taxa de Gravidez , Recuperação Espermática/efeitos adversos , Resultado do Tratamento
2.
Reproduction ; 135(5): 635-47, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18411410

RESUMO

Little is understood about the regulation of gene expression in human preimplantation embryos. We set out to examine the expression in human preimplantation embryos of a number of genes known to be critical for early development of the murine embryo. The expression profile of these genes was analysed throughout preimplantation development and in response to growth factor (GF) stimulation. Developmental expression of a number of genes was similar to that seen in murine embryos (OCT3B/4, CDX2, NANOG). However, GATA6 is expressed throughout preimplantation development in the human. Embryos were cultured in IGF-I, leukaemia inhibitory factor (LIF) or heparin-binding EGF-like growth factor (HBEGF), all of which are known to stimulate the development of human embryos. Our data show that culture in HBEGF and LIF appears to facilitate human embryo expression of a number of genes: ERBB4 (LIF) and LIFR and DSC2 (HBEGF) while in the presence of HBEGF no blastocysts expressed EOMES and when cultured with LIF only two out of nine blastocysts expressed TBN. These data improve our knowledge of the similarities between human and murine embryos and the influence of GFs on human embryo gene expression. Results from this study will improve the understanding of cell fate decisions in early human embryos, which has important implications for both IVF treatment and the derivation of human embryonic stem cells.


Assuntos
Blastocisto/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Peptídeos e Proteínas de Sinalização Intercelular/farmacologia , Diferenciação Celular/genética , Células Cultivadas , Fase de Clivagem do Zigoto/metabolismo , Desenvolvimento Embrionário/efeitos dos fármacos , Desenvolvimento Embrionário/fisiologia , Feminino , Expressão Gênica , Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Fator de Crescimento Semelhante a EGF de Ligação à Heparina , Humanos , Imuno-Histoquímica , Fator de Crescimento Insulin-Like I/farmacologia , Fator Inibidor de Leucemia/farmacologia , Mórula/metabolismo , Reação em Cadeia da Polimerase/métodos , Gravidez , Zigoto/metabolismo
3.
Hum Reprod ; 19(10): 2319-24, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15298971

RESUMO

BACKGROUND: IVF is limited by low success rates and an unacceptably high multiple pregnancy rate. These outcomes would be improved significantly if a single embryo of high viability could be replaced in each treatment cycle, but widespread acceptance of such a policy is hindered by the lack of predictive factors for embryo selection. We have conducted a retrospective clinical study of a novel non-invasive method of embryo selection based on the depletion/appearance of amino acids in the culture medium. METHODS: Fifty-three cycles of IVF treatment using ICSI were studied. Embryos were cultured for 24 h in 4 microl drops of medium containing a physiological mixture of 18 amino acids. The spent medium was analysed for amino acid content by high performance liquid chromatography. RESULTS: The turnover of three amino acids, Asn, Gly and Leu, was significantly correlated with a clinical pregnancy and live birth. These correlations were independent of known predictors, such as female age, basal levels of FSH, embryo cell number and embryo morphological grade. CONCLUSIONS: Non-invasive assay of amino acid turnover has the potential to improve significantly the prospective selection of the most viable embryos, or single embryo, for replacement in an IVF cycle.


Assuntos
Aminoácidos/metabolismo , Blastocisto/fisiologia , Desenvolvimento Embrionário , Fertilização in vitro , Injeções de Esperma Intracitoplásmicas , Adulto , Blastocisto/metabolismo , Feminino , Humanos , Valor Preditivo dos Testes , Gravidez
4.
Hum Reprod ; 19(6): 1448-9, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15163644

RESUMO

Advances in cancer treatment have led to significant improvements in the likelihood of reaching remission and long-term survival for men. Chemo- and radiotherapy-induced infertility are significant treatment side effects. Cryopreservation before the start of treatment enables sperm to be stored, thereby preserving the man's potential fertility. Here, we describe the successful use (with ICSI) of sperm cryopreserved prior to cancer treatment, for a total of 21 years. We believe this to be the longest period of sperm cryopreservation, resulting in a live birth, so far reported in the literature.


Assuntos
Criopreservação , Resultado da Gravidez , Espermatozoides , Teratoma/terapia , Neoplasias Testiculares/terapia , Adolescente , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Feminino , Fertilização in vitro , Humanos , Recém-Nascido , Masculino , Gravidez , Injeções de Esperma Intracitoplásmicas , Teratoma/tratamento farmacológico , Teratoma/radioterapia , Neoplasias Testiculares/tratamento farmacológico , Neoplasias Testiculares/radioterapia , Fatores de Tempo
6.
Br J Cancer ; 87(4): 381-4, 2002 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-12177773

RESUMO

Between 1978 and 1990, 122 men underwent semen analysis before starting sterilising chemotherapy for Hodgkin's disease. Eighty-one (66%) had semen quality within the normal range, 25 were oligospermic (<20 x 10(6) sperm per ml) and five were azoospermic (no sperm in the ejaculate). Semen from 115 men was cryopreserved and after a median follow-up time of 10.1 years, 33 men have utilised stored semen (actuarial rate 27%) and nine partners have become pregnant resulting in 11 live births and one termination for foetal malformation. Actuarial 10 year rates of destruction of semen before death or utilisation and death before utilisation are 19% and 13% respectively. This retrospective cohort study demonstrates that approximately one-quarter of men utilising cryopreserved semen after treatment for Hodgkin's disease obtain a live birth. The high non-utilisation rate is intriguing and warrants further investigation.


Assuntos
Criopreservação , Doença de Hodgkin/tratamento farmacológico , Taxa de Gravidez , Preservação do Sêmen , Antineoplásicos/efeitos adversos , Estudos de Coortes , Feminino , Humanos , Masculino , Gravidez , Técnicas de Reprodução Assistida , Estudos Retrospectivos , Fatores de Tempo
7.
Lancet ; 357(9274): 2080-4, 2001 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-11445100

RESUMO

BACKGROUND: There have been reports suggesting that children born after in-vitro fertilisation by intracytoplasmic sperm injection (ICSI) are at increased risk of neurodevelopmental delay. We have undertaken a case-control study of this issue. METHODS: We studied 208 singleton children conceived by ICSI and a control group of 221 normally conceived singleton children. Children were recruited from 22 fertility centres and local nurseries throughout the UK. Controls were selected to match cases as closely as possible for social class, maternal educational attainment, region, sex, and race. The primary outcome measure was neurodevelopmental scoring; secondary measures were perinatal outcomes, postnatal health, and congenital abnormalities. A single examiner assessed all the children. FINDINGS: A follow-up rate of 90% for the ICSI group was achieved at a mean age of 17 months. No difference between the study children and controls was found in mean neurodevelopmental scores (98.08 [SD 10.93] vs 98.69 [9.99]) or any subscales on the Griffiths' scales of mental development. Perinatal outcome was similar apart from a higher rate of caesarean section (73 [35.1%] vs 53 [24.0%], p=0.015) and a lower mean birthweight (3163 [SD 642] vs 3341 [606] g, p=0.013) in the study group. Rates of major congenital abnormality were also similar overall (ten [4.8%] study vs ten [4.5%] control), although there were significantly more congenital anomalies among children born to fathers with oligozoospermia than in other children. INTERPRETATION: This population study did not show any significant difference between children conceived after ICSI and their naturally conceived peers in terms of physical health and development.


Assuntos
Desenvolvimento Infantil , Injeções de Esperma Intracitoplásmicas , Análise de Variância , Estudos de Casos e Controles , Pré-Escolar , Anormalidades Congênitas/epidemiologia , Feminino , Humanos , Lactente , Recém-Nascido , Doenças do Recém-Nascido/epidemiologia , Masculino , Testes Neuropsicológicos , Gravidez , Resultado da Gravidez , Reino Unido/epidemiologia
8.
Lancet ; 357(9263): 1172-5, 2001 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-11323045

RESUMO

BACKGROUND: Infertility is a common late effect of chemotherapy and radiotherapy, and has a substantial effect on the quality of life for young survivors of cancer. For men, semen cryopreservation is a simple way of preserving reproductive potential but for women, storage of mature eggs rarely proves successful, and the alternative-immediate in vitro fertilisation with cryopreservation of embryos-is not always appropriate. Reimplantation of cryopreserved ovarian tissue has been shown to restore natural fertility in animals. We applied this technique in a woman who had received sterilising chemotherapy for lymphoma. METHODS: A 36-year-old woman underwent a right oophorectomy with cryopreservation of ovarian cortical strips before receiving high-dose CBV chemotherapy for a third recurrence of Hodgkin's lymphoma. 19 months later, when serum sex steroid analysis confimed a postmenopausal state, two ovarian cortical strips were thawed and reimplanted-one onto the left ovary and another at the site of the right ovary. FINDINGS: 7 months after reimplantation of ovarian cortical strips, the patient reported resolution of hot flashes and, for the first time, oestradiol was detected in the serum. This finding was associated with a decrease in the concentrations of follicle-stimulating hormone and luteinising hormone, and ultrasonography revealed a 10 mm thick endometrium, a poorly visualised left ovary, and a 2 cm diameter follicular structure to the right of the midline. The patient had one menstrual period, but by 9 months after the implantation, her sex steroid concentrations had returned to those seen with ovarian failure. INTERPRETATION: Orthotopic reimplantation of frozen/thawed ovarian cortical strips is a well tolerated technique for restoring ovarian function in women treated with sterilising chemotherapy for cancer.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Criopreservação , Doença de Hodgkin/tratamento farmacológico , Infertilidade Feminina/induzido quimicamente , Infertilidade Feminina/cirurgia , Preservação de Órgãos , Ovário , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Bleomicina/administração & dosagem , Ciclofosfamida/administração & dosagem , Doxorrubicina/administração & dosagem , Etoposídeo/administração & dosagem , Feminino , Humanos , Ovariectomia , Ovário/fisiologia , Ovário/transplante , Transplante Autólogo , Vincristina/administração & dosagem
10.
Hum Reprod ; 16(1): 107-109, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11139546

RESUMO

Two cases are reported of successful pregnancies following long-term semen banking prior to chemotherapy and radiotherapy for malignancy. With the first case, the patient banked semen at the age of 20 years prior to chemotherapy for Hodgkin's disease; 11 years later the thawed semen was used for IVF with intracytoplasmic sperm injection (ICSI), resulting in twins being born following the transfer of frozen-thawed embryos. In the second case, the patient banked semen at the age of 17 years prior to chemotherapy and radiotherapy for acute myeloid leukaemia; 8 years later it was used for ICSI, resulting in triplets being born following the transfer of frozen-thawed embryos. These cases support long-term semen banking for men whose future fertility may be compromised by suppression of spermatogenesis secondary to administration of chemo/radiotherapy treatment. The advent of successful ICSI combined with embryo cryopreservation has increased the chance of thawed cryopreserved semen achieving fertilization. Banking of a single ejaculate prior to commencement of chemotherapy/radiotherapy treatment may preserve potential fertility without compromising the oncology treatment.


Assuntos
Criopreservação , Doença de Hodgkin/tratamento farmacológico , Doença de Hodgkin/radioterapia , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/radioterapia , Preservação do Sêmen , Injeções de Esperma Intracitoplásmicas , Adolescente , Antineoplásicos/efeitos adversos , Feminino , Humanos , Masculino , Oligospermia/etiologia , Oligospermia/terapia , Gravidez , Resultado da Gravidez , Espermatogênese/efeitos dos fármacos , Espermatogênese/efeitos da radiação
11.
Lancet ; 355(9212): 1336, 2000 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-10776753

RESUMO

Human embryos cryopreserved after in-vitro fertilisation can be stored initially for 5 years, and the storage period may be extended to a maximum of 10 years. Of 1344 embryos cryopreserved between 1988 and 1994 at two centres in Manchester, 67% (904 embryos) have had to be destroyed at the end of the first 5-year interval, even if the couples involved remain childless.


Assuntos
Criopreservação , Destinação do Embrião , Transferência Embrionária , Fertilização in vitro , Pacientes Desistentes do Tratamento , Inglaterra , Feminino , Regulamentação Governamental , Humanos , Recém-Nascido , Gravidez , Fatores de Tempo
14.
Stud Health Technol Inform ; 68: 343-6, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10724902

RESUMO

This project has been concerned with the comparison of children born as a result of fresh embryo transfer (IVF) with children conceived and born via the natural process. The former included children who were the single outcome of the birth (singletons) and children who were the result of a multiple birth (e.g. twins, triplets). A computer database was established into which was put 23 items of data on each child, making a total of 12,788 items overall. There were 278 "normally conceived" children (controls), 150 IVF Singletons, and 128 children from multiple births. The results show interesting differences in the gestational age at birth, the birth weight, the mode of delivery and the degrees of birth abnormalities and malformations.


Assuntos
Transferência Embrionária , Fertilização in vitro , Computação Matemática , Resultado da Gravidez , Gravidez Múltipla , Peso ao Nascer , Anormalidades Congênitas/epidemiologia , Bases de Dados Factuais , Transferência Embrionária/estatística & dados numéricos , Feminino , Fertilização in vitro/estatística & dados numéricos , Idade Gestacional , Humanos , Recém-Nascido , Gravidez , Gravidez Múltipla/estatística & dados numéricos
15.
Hum Reprod ; 13(11): 3045-8, 1998 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9853853

RESUMO

Insemination with donor spermatozoa is an integral part of infertility treatment. For the last 3 years in our unit, intrauterine insemination with donor spermatozoa (IUID) has been used in preference to vaginal insemination. In this retrospective study, patients were offered an initial course of five single intrauterine inseminations with cryopreserved donor spermatozoa and treatment was then reviewed. A total of 389 patients received 1465 inseminations. In all, 1119 cycles were monitored using luteinizing hormone serum analyses and 346 cycles using the urine home test kits. The clinical pregnancy rate per insemination for the cycles monitored by the serum assay was 18.0% (202/1119) compared with the urine cycles (13.7%, 46/346) (P <05). The pregnancy loss rate was not significantly different (14.4%, 29/202 and 21.7%, 10/46) (serum and urine cycles respectively). The viable clinical pregnancy rate was significantly higher (P <03) for the serum cycles than for the cycles using the urinary monitoring (15.5%, 173/1119 and 10.4%, 36/346 respectively). The cycles monitored by serum assay had a significantly higher cumulative viable clinical pregnancy rate (P <0001) of 70.2% after nine inseminations compared with the urine monitored cycles of 54.8%. The majority of patients opted for the serum cycles, with a minority self-selecting the urine cycles mainly for travelling convenience. The explanation for the significant differences between the viable clinical pregnancy rates per insemination and the cumulative viable clinical pregnancy rates may be due to the sensitivity of the urine home test kit or the patients' interpretation of the result.


Assuntos
Criopreservação , Inseminação Artificial Heteróloga/métodos , Hormônio Luteinizante/sangue , Hormônio Luteinizante/urina , Feminino , Humanos , Infertilidade/terapia , Masculino , Detecção da Ovulação , Gravidez , Resultado da Gravidez , Estudos Retrospectivos
16.
J Steroid Biochem Mol Biol ; 66(4): 171-8, 1998 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9744514

RESUMO

The question of how glucocorticoid, progesterone, androgen, and mineralocorticoid receptors can generate distinct patterns of gene expression despite similar, if not identical, DNA sequence recognition properties is a central question in steroid biology. This study addresses the hypothesis that glucocorticoid and progesterone receptors can differentially utilize the promoter context created by a series of receptor recognition sites. This hypothesis predicts that for different receptors an individual (often suboptimal) binding site contributes to the overall response element activity to a different degree. Therefore, mutations to an individual binding site of a multipartite hormone response element may differentially affect the response to different steroids. This study tests this hypothesis by introducing mutations into a receptor recognition site that is part of a hormone responsive promoter derived from the mouse mammary tumor virus. We find that weakening one site of a multipartite element differentially affects glucocorticoid and progestin signaling both in fibroblasts and in mammary carcinoma cells. A similar test was done in a simplified promoter context comprised only of a TATA box and a pair of receptor recognition sites. Mutations introduced into one of these sites impaired glucocorticoid response more than the progestin response. However, high receptor expression can partially overcome the effect of some target site mutations. Thus both receptor expression levels and the inherent ability to utilize the context created by a multipartite response element contribute to quantitative differences in the response to receptors that share DNA sequence recognition properties.


Assuntos
Regulação Neoplásica da Expressão Gênica , Vírus do Tumor Mamário do Camundongo/genética , Regiões Promotoras Genéticas , Receptores de Glucocorticoides/metabolismo , Receptores de Progesterona/metabolismo , Animais , Sequência de Bases , Neoplasias da Mama , Cloranfenicol O-Acetiltransferase/genética , Dexametasona/farmacologia , Feminino , Fibroblastos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Genes Reporter , Humanos , Luciferases/genética , Camundongos , Mutagênese Sítio-Dirigida , Receptores de Glucocorticoides/genética , TATA Box , Ativação Transcricional , Transfecção , Células Tumorais Cultivadas
17.
Mol Endocrinol ; 12(6): 891-8, 1998 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9626664

RESUMO

Hormone response elements (HREs) are considered enhancers, activating transcription in a relatively position- and orientation-independent fashion. Upon binding to an HRE, steroid receptors presumably contact coactivators and/or proteins associated with the transcription initiation complex. As a receptor target site is moved further from a fixed position such as the TATA box, not only will the spatial separation of the receptor with respect to its interaction partners change, so will the orientation due to the rotation of the DNA helix. Additional constraints may be imposed by the assembly of DNA into chromatin. Therefore, we have endeavored to test rigorously the assertion that HRE action is position independent. We have constructed a series of 42 chloramphenicol acetyltransferase expression vectors that contain a single progesterone/glucocorticoid receptor-binding site separated from a TATA box by 4 to 286 bp. The enhancer activity of the HRE was assessed after transient transfection of progesterone receptor-expressing fibroblasts. We find that the position of the HRE has a dramatic influence on induction by progestins. When closely juxtaposed to the TATA box, the HRE was unable to support a hormone response, perhaps due to direct steric hindrance with the transcription initiation complex. Full activity was gained by moving the HRE 10 bp further from the TATA sequence. As the HRE was moved incrementally further, activity remained near maximal over the next 26 bp. HRE activity then declined over the subsequent 26 bp and remained low for another 2.5 helical turns. Surprisingly, a narrow window of HRE activity occurred at an HRE-TATA box separation of 90-100 bp. Little or no hormone-induced transcriptional activity was observed when the HRE was positioned further from the TATA box. The addition of a second HRE or a basal (nuclear factor-1) element failed to relieve this constraint. A similar series of experiments was carried out in a mammary carcinoma cell line that expressed high levels of both glucocorticoid and progestin receptors. Data in these cells indicate that glucocorticoids and progestins supported a similar HRE position-activity profile, but this pattern of HRE activity was quite distinct from that seen in fibroblasts. This may be indicative of cell type-specific interactions between steroid receptors and adapter/coactivator proteins or cell type-specific activities such as acetylases or deacetylases participating in the steroid response.


Assuntos
Dexametasona/farmacologia , Elementos Facilitadores Genéticos , Regulação da Expressão Gênica/efeitos dos fármacos , Congêneres da Progesterona/farmacologia , Promegestona/farmacologia , Receptores de Glucocorticoides/genética , Receptores de Progesterona/genética , Sequência de Bases , Sítios de Ligação , Neoplasias da Mama/patologia , Cloranfenicol O-Acetiltransferase/biossíntese , Cloranfenicol O-Acetiltransferase/genética , Feminino , Fibroblastos , Genes Reporter , Vetores Genéticos/genética , Humanos , Dados de Sequência Molecular , Receptores de Glucocorticoides/biossíntese , Receptores de Progesterona/biossíntese , TATA Box , Transcrição Gênica
18.
Hum Reprod ; 12(3): 542-7, 1997 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9130756

RESUMO

A total of 364 consecutive patients requesting in-vitro fertilization (IVF) treatment were divided randomly into two groups. In the first group, two embryos in the original IVF cycle were allowed to divide prior to transfer, with any remaining embryos being cryopreserved at the pronucleate (PN) stage. In the second group, all the embryos were allowed to divide to the early cleavage (EC) stage, and the best two replaced; any suitable remaining embryos were frozen at the 2- to 4-cell stage. A total of 134 cycles (36.8%) fulfilled the study criteria for a fresh embryo replacement and supernumerary embryos cryopreserved. In the PN group, 72 out of 182 (39.6%) patients had a fresh embryo replacement accompanied by embryo cryopreservation, which was not significantly different from the EC group (62/182; 34.1%). The livebirth rate per fresh embryo transfer in the EC group (17/62; 27.4%) was significantly higher than that for the PN group (8/72; 11.1%; P < 0.05). Embryo survival following thawing was similar for the PN (96/129; 74.4%) and EC (79/102; 77.4%) stages. Although not significant, the livebirth rate following the transfer of thawed embryos was higher in the PN group (11/44; 25.0%) than in the EC group (4/38; 10.5%). Following one fresh and two freeze-thaw embryo replacements, the observed cumulative viable pregnancy rates were comparable for patients in both the PN (40.2%) and EC (41.1%) groups.


Assuntos
Criopreservação , Transferência Embrionária/métodos , Embrião de Mamíferos , Fertilização in vitro/métodos , Adulto , Feminino , Humanos , Masculino , Gravidez
19.
Arch Dis Child Fetal Neonatal Ed ; 76(2): F70-4, 1997 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9135283

RESUMO

AIMS: To compare the outcome in in vitro fertilisation (IVF) children (after fresh embryo transfer) from multiple and singleton births with one another, and with normally conceived control children. METHODS: A cohort of 278 children (150 singletons, 100 twins, 24 triplets and four quadruplets), conceived by IVF after three fresh embryos had been transferred, born between October 1984 and December 1991, and 278 normally conceived control children (all singletons), were followed up for four years after birth. They were assessed for neonatal conditions, minor congenital anomalies, major congenital malformations, cerebral palsy and other disabilities. Control children, all born at term, were matched for age, sex and social class. RESULTS: The ratio of male:female births was 1.03. Forty six per cent of IVF children were from multiple births; 34.9% were from preterm deliveries; and 43.2% weighed less than 2500 g at birth. The IVF singletons were on average born one week earlier than the controls, weighed 400 g less, and had a threefold greater chance of being born by caesarean section. The higher percentage of preterm deliveries was largely due to multiple births and they contributed to neonatal conditions in 45.0% of all IVF children. The types of congenital abnormalities varied: 3.6% of IVF children and 2.5% of controls had minor congenital anomalies, and 2.5% of IVF children and none of the controls had major congenital malformations. The numbers of each specific type of congenital abnormality were small and were not significantly related to multiple births. IVF children (2.1%) and 0.4% of the controls had mild/moderate disabilities. They were all from multiple births, including two children with cerebral palsy who were triplets. CONCLUSIONS: The outcome of IVF treatment leading to multiple births is less satisfactory than that in singletons because of neonatal conditions associated with preterm delivery and disabilities in later childhood. A reduction of multiple pregnancies by limiting the transfer of embryos to two instead of three remains a high priority.


Assuntos
Transferência Embrionária , Fertilização in vitro , Resultado da Gravidez , Paralisia Cerebral , Cesárea , Estudos de Coortes , Anormalidades Congênitas , Feminino , Humanos , Recém-Nascido de Baixo Peso , Recém-Nascido , Recém-Nascido Prematuro , Masculino , Gravidez , Estudos Prospectivos , Razão de Masculinidade , Trigêmeos , Gêmeos
20.
Crit Rev Eukaryot Gene Expr ; 7(1-2): 43-59, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9034714

RESUMO

The estrogen steroid hormone receptor (ER) is a member of a family of related hormone-inducible transcriptional regulators. The function of these receptors is dependent on multiple protein-protein interactions with other cellular polypeptides. These contacts regulate the four steps in the receptor "life cycle": synthesis and nuclear transport, priming/storage, activation, and recycling. Each of these steps is mediated by the formation of distinct protein complexes and results in a temporal and spatial regulation of ER activity. This review focuses on the cellular proteins that interact with the ER, and the role that these interactions are believed to play in the regulation of ER.


Assuntos
Receptores de Estrogênio/metabolismo , Animais , Núcleo Celular/metabolismo , Cromatina/metabolismo , Citoplasma/metabolismo , Dimerização , Proteínas Fúngicas/metabolismo , Humanos , Proteínas Nucleares/metabolismo , Fosforilação , Ligação Proteica , Esteroides/farmacologia , Transcrição Gênica
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